The regulation of endo-lysosomal trafficking, growth and exosome biogenesis bydevelopmental signalling cascades. (360G-Wellcome-102347_Z_13_Z)

Late endosomes and lysosomes, intracellular compartments often considered to be sites for macromolecular degradation, have recently been implicated in other fundamental cell biological processes. For example, they regulate growthand biogenesis of secreted vesicles called exosomes, which have postulated roles in development. How these processes and membrane trafficking in endo-lysosomes are linked to developmental signals that control them is poorlyunderstood. Building on my preliminary results using a genetic model with giant endo-lysosomes, the Drosophila secondary cell, I will further characterise the regulation of endo-lysosomal functions by developmental (growth factor) signalling cascades and DNA binding proteins in the steroid receptor family. I will also explore whether there are different populations of exosomes in secondary cells that are differentially regulated by growth factor signals, and whether this regulation is dependent on a feedback mechanism involving loading growth factor signalling components into secreted exosomes. The kinase complex mTORC1 is thought to mediate endo-lysosomal